Showing papers in "Clinical Oral Investigations in 2020"

Coronavirus COVID-19 impacts to dentistry and potential salivary diagnosis

Abstract: A novel coronavirus (COVID-19) is associated with humanto-human transmission. The COVID-19 was recently identified in saliva of infected patients. In this point-of-view article, we discuss the potential of transmission via the saliva of this virus. The COVID-19 transmission via contact with droplets and aerosols generated during dental clinical procedures is expected. There is a need to increase investigations to the detection of COVID-19 in oral fluids and its impact on the transmission of this virus, which is crucial to improve effective strategies for prevention, especially for dentists and healthcare professionals that perform aerosol-generating procedures. Saliva can have a pivotal role in the human-to-human transmission, and non-invasive salivary diagnostics may provide a convenient and cost-effective point-of-care platform for the fast and early detection of COVID-19 infection.

Evaluation of adhesion of Streptococcus mutans, plaque accumulation on zirconia and stainless steel crowns, and surrounding gingival inflammation in primary molars: randomized controlled trial.

Abstract: To evaluate the adhesion of Streptococcus mutans to preformed zirconia and stainless steel crowns and compare plaque accumulation and gingival inflammation over a period of 1 year. Thirty children between 6 to 9 years with pulpectomised bilateral mandibular primary second molars were randomly divided into zirconia/stainless steel groups. Plaque was collected from the crowns using swabs at 3, 6, 9, and 12 months. Gingival and plaque index were recorded at all follow-ups. S. mutans was cultured on tryptone-yeast-cysteine-sucrose-bacitracin agar, and organisms were expressed as colony-forming units. Within-group analysis was performed using repeated measures ANOVA and between-groups using the independent T test. S. mutans were found in significantly higher numbers on the stainless steel crowns as compared with zirconia crowns at all the follow-ups. Gingival inflammation and plaque index scores were also significantly higher around the stainless steel crowns as compared with zirconia at the end of 12 months follow-up. Adhesion of S. mutans to stainless steel crowns was significantly greater when compared with zirconia, and minimal gingival inflammation and plaque accumulation was found in the tooth restored with zirconia crowns as compared with stainless steel crowns. Preformed zirconia crowns prevents adhesion of S. mutans onto its surface, and reduces plaque accumulation around the crown, inflammation of surrounding gingiva compared to conventional stainless-steel crowns. Pediatric zirconia crowns could help in reducing the overall microbial density and prevalence in the oral cavity, thus reducing the caries risk in the long term.

Is the oral cavity relevant in SARS-CoV-2 pandemic?

Abstract: Recent scientific evidences suggest a relevant role of the oral cavity in the transmission and pathogenicity of SARS-CoV-2 A literature search was performed in PubMed, up to April 30, 2020, focusing on SARS-CoV-2, COVID-19, oral cavity, and antimicrobial agents Oral viral load of SARS-CoV-2 has been associated with the severity of COVID-19, and thus, a reduction in the oral viral load could be associated with a decrease in the severity of the condition Similarly, a decrease in the oral viral load would diminish the amount of virus expelled and reduce the risk of transmission, since (i) during the first 10 days, the virus mainly accumulates at the nasal, oral, and pharyngeal area; (ii) the number of angiotensin-converting enzyme (ACE2) receptor is greater in the salivary glands as compared with the lungs; and (iii) salivary droplets represent the most relevant transmission route To reduce the oral viral load, antiseptic agents may be used, although the evidence on its efficacy is indirect and weak Antiseptic mouth rinses, such as those containing cetylpyridinium chloride or povidone-iodine, may be able to decrease the severity of COVID-19 by reducing oral viral load in infected subjects and decreasing the risk of transmission by limiting viral load in droplets, generated in normal life, or in aerosols, produced during dental procedures Well-designed clinical and preclinical research must be conducted to support these hypotheses Antiseptic mouth rinses may help in decreasing the severity of COVID-19 and in reducing the risk of transmission

Fracture load of 3D-printed fixed dental prostheses compared with milled and conventionally fabricated ones: the impact of resin material, build direction, post-curing, and artificial aging-an in vitro study.

Abstract: To investigate the impact of 3D print material, build direction, post-curing, and artificial aging on fracture load of fixed dental prostheses (FDPs). Three-unit FDPs were 3D-printed using experimental resin (EXP), NextDent C&B (CB), Freeprint temp (FT), and 3Delta temp (DT). In the first part, the impacts of build direction and artificial aging were tested. FDPs were manufactured with their long-axis positioned either occlusal, buccal, or distal to the printer’s platform. Fracture load was measured after artificial aging (H2O: 21 days, 37 °C). In the second part, the impact of post-curing was tested. FDPs were post-cured using Labolight DUO, Otoflash G171, and LC-3DPrint Box. While the positive control group was milled from TelioCAD (TC), the negative control group was fabricated from a conventional interim material Luxatemp (LT). The measured initial fracture loads were compared with those after artificial aging. Each subgroup contained 15 specimens. Data were analyzed using Kolmogorov-Smirnov test, one-way ANOVA followed by Scheffe post hoc test, t test, Kruskal-Wallis test, and Mann-Whitney U test (p < 0.05). The univariate ANOVA with partial eta squared (ηP2) was used to analyze the impact of test parameters on fracture load. Specimens manufactured with their long-axis positioned distal to the printer’s platform showed higher fracture load than occlusal ones (p = 0.049). The highest values were observed for CB, followed by DT (p < 0.001). EXP showed the lowest values, followed by FT (p < 0.001). After artificial aging, a decrease of fracture load for EXP (p < 0.001) and DT (p < 0.001) was observed. The highest impact on values was exerted by interactions between 3D print material and post-curing unit (ηP2 = 0.233, p < 0.001), followed by the 3D print material (ηP2 = 0.219, p < 0.001) and curing device (ηP2 = 0.108, p < 0.001). Build direction, post-curing, artificial aging, and material have an impact on the mechanical stability of printed FDPs. The correct post-curing strategy is mandatory to ensure mechanical stability of 3D-printed FDPs. Additively manufactured FDPs are more prone to artificial aging than conventionally fabricated ones.

Health services provision of 48 public tertiary dental hospitals during the COVID-19 epidemic in China.

Abstract: To assess the status of health services provision of public tertiary dental hospitals during the COVID-19 epidemic in China and to evaluate the regional difference of telehealth. The health services provision of public tertiary dental hospitals in China mainland during the COVID-19 epidemic was inquired. The status of non-emergency dental services, emergency dental services, and online professional consultation and the hospitals’ geographical distribution were recorded and analyzed. All the 48 public tertiary dental hospitals suspended general non-emergency dental treatment while providing emergency dental services only. Ninety percent of them notified the change of dental services online, and 69% of them offered free online professional consultations. The penetration rate of online technology was significantly higher in the eastern region than that of the central and western regions. There was a significant change in the health service provision of Chinese public tertiary dental hospitals during the COVID-19 epidemic and wider use of telehealth in the eastern region. This report demonstrated that dental health services were significantly affected by the COVID-19 epidemic in China, which might lead to a long-time impact on dental care in the future.

Accuracy of full-arch digital impressions: an in vitro and in vivo comparison.

Abstract: Comparison of full-arch digital impressions to conventional impressions in vitro and in vivo. A straight metal bar was fixed between the second upper molars as a reference structure in the mouth of a voluntary patient and a corresponding polymer model. The following digitalization methods were applied: (1) the maxilla was digitized in vivo 12 times with the iTero Element (P-SCAN); (2) the maxilla was captured in vivo 12 times by conventional impression and the impression was digitized by a desktop scanner (P-IMP); (3) the impressions were poured and the 12 referring gypsum master-casts were scanned with the same desktop scanner (P-CAST); (4) the polymer model was digitized in vitro 12 times with the iTero Element (M-SCAN); (5) the polymer model was captured in vitro 12 times by conventional impression and the impression was digitized by a desktop scanner (M-IMP); (6) the impressions were poured and the 12 referring gypsum master-casts were scanned with the same desktop scanner (M-CAST). Datasets were exported and metrically analyzed (Geomagic Control X) to determine three-dimensional length aberration and angular distortion versus the reference structure. Mann–Whitney U test was implemented to detect differences (p < 0.05). For multiple accuracy parameters, P-SCAN and M-SCAN showed similar or superior results compared to the other digitalization methods. The following length deviations were found: M-SCAN (− 55 to 80 μm), M-IMP (110 to 329 μm), M-CAST (88 to 178 μm), P-SCAN (− 67 to 76 μm), P-IMP (125–320 μm), and P-CAST (92–285 μm). Within the limitations of this study, the iTero-scan seems to be a valid alternative to conventional impressions for full arches. Intraoral scanners are more and more used in daily routine; however, little is known about their accuracy when it comes to full-arch scans. Under optimum conditions, the direct digitalization using the iTero Element intraoral scanning device results in the same and for single parameters (arch width and arch distortion) even in higher accuracy than the indirect digitalization of the impression or the gypsum cast using a desktop scanner.

Secondary caries: prevalence, characteristics, and approach.

Abstract: The objectives of this cross-sectional survey were to determine the prevalence of secondary caries (SC) in general population, to identify patient- and material-related factors which may affect the prevalence, and to describe some clinical characteristics of SC lesions. A total of 4036 restorations in 450 patients, who visited the university dental clinic for a regular (half) yearly checkup, were examined clinically (and radiographically) for the presence of SC. Clinical characteristics of the detected SC lesions (size, activity, and location) and the planned treatment were recorded. In addition, patients’ caries-risk status was assessed according to the modified “cariogram” model. In total, 146 restorations were diagnosed with SC, which gives an overall prevalence of 3.6%. Restorative material, restoration class, patient’s caries risk, and smoking habits were shown to be important factors, as SC prevalence was significantly higher with composites, class II restorations, high-caries-risk patients, and smokers. Restorations’ gingival margins were most frequently affected by SC. The largest number of restorations with SC (72%) was scheduled for the replacement. Prevalence of SC was higher with composite than with amalgam restorations, irrespective of the patient’s caries-risk status. Gingival margins of class II, including MOD restorations, seem to be the place of less resistance to SC development. Management of SC seems to place a considerable burden on the health care workforce and expenditure. Secondary caries (SC) is considered to be the main cause of dental restoration failure and one of the biggest clinical challenges related to dental composites. Nevertheless, its prevalence in daily practice is still not clear, which impedes an accurate estimation of its impact on health care costs.

A prospective clinical pilot study on the effects of a hydrogen peroxide mouthrinse on the intraoral viral load of SARS-CoV-2.

Abstract: SARS-CoV-2 is mainly transmitted by inhalation of droplets and aerosols. This puts healthcare professionals from specialties with close patient contact at high risk of nosocomial infections with SARS-CoV-2. In this context, preprocedural mouthrinses with hydrogen peroxide have been recommended before conducting intraoral procedures. Therefore, the aim of this study was to investigate the effects of a 1% hydrogen peroxide mouthrinse on reducing the intraoral SARS-CoV-2 load. Twelve out of 98 initially screened hospitalized SARS-CoV-2-positive patients were included in this study. Intraoral viral load was determined by RT-PCR at baseline, whereupon patients had to gargle mouth and throat with 20 mL of 1% hydrogen peroxide for 30 s. After 30 min, a second examination of intraoral viral load was performed by RT-PCR. Furthermore, virus culture was performed for specimens exhibiting viral load of at least 103 RNA copies/mL at baseline. Ten out of the 12 initially included SARS-CoV-2-positive patients completed the study. The hydrogen peroxide mouthrinse led to no significant reduction of intraoral viral load. Replicating virus could only be determined from one baseline specimen. A 1% hydrogen peroxide mouthrinse does not reduce the intraoral viral load in SARS-CoV-2-positive subjects. However, virus culture did not yield any indication on the effects of the mouthrinse on the infectivity of the detected RNA copies. The recommendation of a preprocedural mouthrinse with hydrogen peroxide before intraoral procedures is questionable and thus should not be supported any longer, but strict infection prevention regimens are of paramount importance. German Clinical Trials Register (ref. DRKS00022484)

Bioadhesion in the oral cavity and approaches for biofilm management by surface modifications.

Abstract: All soft and solid surface structures in the oral cavity are covered by the acquired pellicle followed by bacterial colonization. This applies for natural structures as well as for restorative or prosthetic materials; the adherent bacterial biofilm is associated among others with the development of caries, periodontal diseases, peri-implantitis, or denture-associated stomatitis. Accordingly, there is a considerable demand for novel materials and coatings that limit and modulate bacterial attachment and/or propagation of microorganisms. The present paper depicts the current knowledge on the impact of different physicochemical surface characteristics on bioadsorption in the oral cavity. Furthermore, it was carved out which strategies were developed in dental research and general surface science to inhibit bacterial colonization and to delay biofilm formation by low-fouling or “easy-to-clean” surfaces. These include the modulation of physicochemical properties such as periodic topographies, roughness, surface free energy, or hardness. In recent years, a large emphasis was laid on micro- and nanostructured surfaces and on liquid repellent superhydrophic as well as superhydrophilic interfaces. Materials incorporating mobile or bound nanoparticles promoting bacteriostatic or bacteriotoxic properties were also used. Recently, chemically textured interfaces gained increasing interest and could represent promising solutions for innovative antibioadhesion interfaces. Due to the unique conditions in the oral cavity, mainly in vivo or in situ studies were considered in the review. Despite many promising approaches for modulation of biofilm formation in the oral cavity, the ubiquitous phenomenon of bioadsorption and adhesion pellicle formation in the challenging oral milieu masks surface properties and therewith hampers low-fouling strategies. Improved dental materials and surface coatings with easy-to-clean properties have the potential to improve oral health, but extensive and systematic research is required in this field to develop biocompatible and effective substances.

Effect of platelet-rich fibrin on cell proliferation, migration, differentiation, inflammation, and osteoclastogenesis: a systematic review of in vitro studies

Abstract: To systematically assess the effects of platelet-rich fibrin (PRF) on in vitro cellular behavior. A systematic electronic search using MEDLINE database was performed. In vitro studies using PRF were considered and articles published up to June 31, 2018 were screened. Eligible studies were selected based on the use of human PRF. In total, 1746 titles were identified with the search terms, from these 37 met the inclusion criteria and were chosen for data extraction. In addition, 16 new studies, mainly published in 2019, were also included in the analysis resulting in 53 studies. No meta-analysis could be performed due to the heterogeneity of study designs. Included studies show that PRF enhances proliferation, migration, adhesion, and osteogenic differentiation on a variety of cell types along with cell signaling activation. Furthermore, PRF reduces inflammation, suppresses osteoclastogenesis, and increases the expression of various growth factors in mesenchymal cells. Despite some notable differences of the studies, the overall findings suggest a positive effect of PRF on cell proliferation, migration, adhesion, differentiation, and inflammation pointing towards a therapeutic potential in regenerative dentistry. PRF serves as a reservoir of bioactive molecules to support wound healing and bone regeneration. Although the cellular mechanisms by which PRF supports the clinical outcomes remain unclear, in vitro research provides possible explanations. This systematic review aims to provide an update of the existing research on how PRF affects basic physiological processes in vitro. The overall findings suggest that PRF induces cell proliferation, migration, adhesion, and differentiation along with possessing anti-inflammatory properties further supporting its therapeutic potential in wound healing and bone regeneration.

Secondary caries: what is it, and how it can be controlled, detected, and managed?

Abstract: To assess how to control, detect, and treat secondary caries. This review serves to inform a joint ORCA/EFCD consensus process. Systematic and non-systematic reviews were performed or consulted and narratively synthesized. Secondary (or recurrent) caries is defined as a lesion associated with restorations or sealants. While the restorative material itself has some influence on secondary caries, further factors like the presence and size of restoration gaps, patients’ caries risk, and the placing dentist’s experience seem more relevant. Current detection methods for secondary caries are only sparsely validated and likely prone for the risk of over-detection. In many patients, it might be prudent to prioritize specific detection methods to avoid invasive overtreatment. Detected secondary caries can be managed either by repair of the defective part of the restoration or its complete replacement. There is sparse data towards the nature of secondary caries and how to control, detect, and treat it. Despite often claimed to be a major complication of restorations, there is surprisingly little data on secondary caries. Longer-term studies may be needed to identify differences in secondary caries risk between materials and to identify characteristic features of progressive lesions (i.e., those in need of treatment).

Association between periodontitis and glycosylated haemoglobin before diabetes onset: a cross-sectional study.

Abstract: The aim of the present cross-sectional study was to investigate the association between serum glycosylated haemoglobin (HbA1c) levels and periodontal status in patients with periodontitis (CP) and periodontally healthy controls. Furthermore, the objectives were to determine if the periodontitis influenced the serum HbA1c levels. A total of 93 patients with CP and 95 periodontally healthy subjects were enrolled in the present study using a cross-sectional design. At baseline, patients were examined and characterized on a regular basis for blood serum parameters and non-fasting blood samples levels. In all patients, a full periodontal examination was performed and clinical attachment loss (CAL) was the primary outcome variable chosen. The spearman correlation, a stepwise multivariable linear regression, and Jonckheere-Terpstra tests were applied in order to assess the relationship between HbA1c levels and periodontitis. Patients in the CP group presented a significantly higher median serum level of HbA1c [40.9 (31.2; 45.6) mmol/mol)] compared to patients in the healthy control group [35.3 (29.6; 38.6) mmol/mol)] (p < 0.001). HbA1c levels were negatively correlated with the number of teeth and positively correlated with C-reactive protein levels and all periodontal parameters (p < 0.001). Moreover, there was a significant decrease in the number of teeth when HbA1c levels increased (P-trend < 0.001), while there was a significant increase in periodontal parameters (CAL, p = 0.002); PD, p = 0.008; BOP, p < 0.001) when levels of HbA1c increased. Patients with CP and undiagnosed diabetes presented significantly higher serum levels of HbA1c compared to periodontally healthy controls. Moreover, the presence of periodontitis was positively correlated with serum HbA1c levels before diabetes onset. HbA1c levels were positively correlated with the severity of periodontitis before diabetes onset.

Flexural strength, biocompatibility, and antimicrobial activity of a polymethyl methacrylate denture resin enhanced with graphene and silver nanoparticles.

Abstract: The study evaluates the effect of adding graphene-Ag nanoparticles (G-AgNp) to a PMMA auto-polymerizing resin, with focus on antibacterial activity, cytotoxicity, monomer release, and mechanical properties. Auto-polymerizing acrylic resin (M) was loaded with 1 wt% G-AgNp (P1) and 2 wt% G-AgNp (P2). Methyl methacrylate monomer release (MMA) was measured after immersion of the samples in chloroform and cell medium respectively. Cell viability was assessed on dysplastic oral keratinocytes (DOK) and dental pulp stem cells. Oxidative stress and inflammatory response following exposure of dysplastic oral keratinocytes to the experimental resins was evaluated. Antibacterial activity against Staphylococcus aureus, Streptococcus mutans and Escherichia coli and also flexural strength of the resins were assessed. Residual monomer: For samples immersed in chloroform, MMA concentration reached high levels, 10.27 μg/g for sample P1; MMA increased at higher G-AgNp loading; 0.63 μg/g MMA was found in medium for P1, and less for sample P2. Cell viability: Both cell lines displayed a viability decrease, but remained above 75%, compared to controls, when exposed to undiluted samples. Inflammation: proinflammatory molecule TNF-α decreased when DOK cultures were exposed to G-AgNp samples. MDA levels indicated increased oxidative stress damage in cells treated with PMMA, confirmed by the antioxidant mechanism activation, while samples containing G-AgNp induced an antioxidant effect. All tested samples showed antibacterial properties against Gram-positive bacteria. Samples containing G-AgNp also exhibited bactericide action on E. coli. Mechanical properties: both samples containing G-AgNp improved flexural strength compared to the sample resin, measured through elastic strength parameters. PMMA resin loaded with G-AgNp presents promising antibacterial activity associated with minimal toxicity to human cells, in vitro, as well as improved flexural properties. These encouraging results obtained in vitro support further in vivo investigation, to thoroughly check whether the PMMA loaded with graphene-silver nanoparticles constitute an improvement over current denture materials.

Comparison of platelet-rich fibrin (PRF) produced using 3 commercially available centrifuges at both high (~ 700 g) and low (~ 200 g) relative centrifugation forces

Abstract: Platelet-rich fibrin (PRF) has gained tremendous momentum in recent years as a natural autologous growth factor derived from blood capable of stimulating tissue regeneration. Owing to its widespread use, many companies have commercialized various centrifugation devices with various proposed protocols. The aim of the present study was to compare 3 different commercially available centrifuges at both high and low g-force protocols. PRF was produced on three commercially available centrifuges including the IntraSpin Device (IntraLock), the Duo Quattro (Process for PRF), and Salvin (Salvin Dental). Two separate protocols were tested on each machine including the original leukocyte and platelet-rich fibrin (L-PRF) protocol (~ 700 RCF max (~ 400 RCF clot) for 12 min) as well as the advanced platelet-rich fibrin (A-PRF+) protocol (~ 200 g RCF max (~ 130 g RCF clot) for 8 min). Each of the tested groups was compared for cell numbers, growth factor release, scanning electron microscopy (SEM) for morphological differences, and clot size (both weight and length/width). The present study found that PRF clots produced utilizing the low-speed centrifugation speeds (~ 200 g for 8 min) produce clots that (1) contained a higher concentration of evenly distributed platelets, (2) secreted higher concentrations of growth factors over a 10 day period, and (3) were smaller in size. This was irrespective of the centrifugation device utilized and consistently observed on all 3 devices. The greatest impact was found between the protocols utilized (up to a 200%). Interestingly, it was further revealed that the centrifugation tubes used had a much greater impact on the final size outcome of PRF clots when compared to centrifugation devices. It was found that, in general, the Process for PRF tubes produced significantly greater-sized clots when compared to other commercially available tubes. The Salvin Dental tubes also produced significantly greater PRF clots when compared to the IntraLock tubes on each of the tested centrifugation devices. The present study demonstrated the reproducibility of a scientific concept (reduction in RCF produces PRF clots with more evenly distributed cells and growth factors) utilizing different devices. Furthermore, (and until now overlooked), it was revealed for the first time that the centrifugation tubes are central to the quality production of PRF. Future research investigating tube characteristics thus becomes critically important for the future optimization of PRF. This is the first study to reveal the marked impact of centrifugation tubes on the final production of PRF. Future study thus becomes markedly important to further optimize the quality of PRF-based matrices. It was further found that little variability existed between the centrifugation devices if optimized centrifugation protocols (lower centrifugation speeds) were utilized.

Cytocompatibility, bioactivity potential, and ion release of three premixed calcium silicate-based sealers

Abstract: Compositional modifications may alter the biological and physicochemical characteristics of calcium silicate-based sealers (CSBS) and, ultimately, their bioactivity. The main objective of this study was to evaluate the biological properties of three CSBS: EndoSequence BC Sealer, Ceraseal, and Endoseal mineral trioxide aggregate. Human periodontal ligament stem cells (hPDLSCs) were exposed to several eluates of CSBS. The ion release profile and pH were determined, and metabolic activity and cell migration were assessed using the MTT and wound healing assays. hPDLSCs were cultured in direct contact with the surface of each material, and cell morphology and attachment were analyzed by scanning electron microscopy (SEM). Bioactivity potential was assessed by RT-qPCR and mineralization assays. Statistical differences between biomaterials were assessed using one- or two-way ANOVA (α < 0.05). All materials showed an alkaline pH, although Endoseal exhibited a significantly higher pH compared with the other CSBS (p < 0.05). Ceraseal released significantly more Ca2+ (p < 0.05) than EndoSequence BC Sealer and Endoseal. Interestingly, Endoseal induced a significant reduction in cell viability and cell migration compared with the control (p < 0.001). Moreover, SEM showed abundant cells adhering to EndoSequence BC Sealer and Ceraseal surfaces, whereas very few round cells were detected on the surface of Endoseal. Finally, Ceraseal and EndoSequence induced ALP, CAP, and CEMP-1 expression and a significantly higher mineralization capacity than Endoseal (***p < 0.001). The eluates from EndoSequence BC Sealer and Ceraseal displayed higher cell viability, cell attachment, cell migration rates, and ion release rates than Endoseal. Ceraseal and EndoSequence BC Sealer exhibited significantly more gene expression and mineralization capacity than Endoseal. The results obtained in the present work suggest that EndoSequence BC Sealer and Ceraseal possess biological properties that make them suitable materials for root canal treatment.

Use of platelet-rich fibrin for the treatment of gingival recessions: a systematic review and meta-analysis.

Abstract: The aim of this systematic review and meta-analysis was to compare the use of platelet-rich fibrin (PRF) with other commonly utilized treatment modalities for root coverage procedures. The eligibility criteria comprised randomized controlled trials (RCTs) comparing the performance of PRF with that of other modalities in the treatment of Miller class I or II (Cairo RT I) gingival recessions. Studies were classified into 5 categories as follows: (1) coronally advanced flap (CAF) alone vs CAF/PRF, (2) CAF/connective tissue graft (CAF/CTG) vs CAF/PRF, (3) CAF/enamel matrix derivative (CAF/EMD) vs CAF/PRF, (4) CAF/amnion membrane (CAF/AM) vs CAF/PRF, and (5) CAF/CTG vs CAF/CTG/PRF. Studies were evaluated for percentage of relative root coverage (rRC; primary outcome), clinical attachment level (CAL), keratinized mucosa width (KMW), and probing depth (PD) (secondary outcomes). From 976 articles identified, 17 RCTs were included. The use of PRF statistically significantly increased rRC and CAL compared with CAF alone. No change in KMW or reduction in PD was reported. Compared with PRF, CTG resulted in statistically significantly better KMW and RC. No statistically significant differences were reported between the CAF/PRF and CAF/EMD groups or between the CAF/PRF and CAF/AM groups for any of the investigated parameters. The use of CAF/PRF improved rRC and CAL compared with the use of CAF alone. While similar outcomes were observed between CAF/PRF and CAF/CTG for CAL and PD change, the latter group led to statistically significantly better outcomes in terms of rRC and KTW. In summary, the use of PRF in conjunction with CAF may represent a valid treatment modality for gingival recessions exhibiting adequate baseline KMW. The data indicate that the use of PRF in conjunction with CAF statistically significantly improves rRC when compared with CAF alone but did not improve KMW. Therefore, in cases with limited baseline KMW, the use of CTG may be preferred over PRF.

Effect of a hydrophobic bonding resin on the 36-month performance of a universal adhesive—a randomized clinical trial

Abstract: To evaluate if the addition of a layer of a hydrophobic bonding resin to the recommended application sequence of a universal adhesive improves the respective clinical behavior in non-carious cervical lesions (NCCLs) after 36 months. Scotchbond Universal Adhesive (SBU, 3M Oral Care) was applied in NCCLs of 39 subjects using four adhesion strategies: (1) three-step ER (etch-and-rinse), (2) two-step ER, (3) two-step SE (self-etch), and (4) one-step SE. An extra layer of a hydrophobic bonding resin was applied for strategies three-step ER and two-step SE. The same composite resin (Filtek Supreme XTE, 3M Oral Care) was used for all strategies. Restorations were evaluated at baseline and 18 and 36 months using the modified United States Public Health Service (USPHS) criteria. Kruskal–Wallis, Mann–Whitney U, Friedman, and Wilcoxon non-parametric tests were computed. The cumulative failure rate was 8.6%. The 36-month retention rates were 100% for both 3-ER and 2-ER, 76.0% for 2-SE, and 86.2% for 1-SE. A lower retention rate was observed for two-step SE at 36 months compared with both three-ER (p < 0.01) and two-ER (p < 0.01). Identical retention rates were measured for the two SE groups. When retention rate was compared at baseline versus 36 months for each adhesion strategy, a significant decrease was observed for 2-SE. The restorations performed with 3-ER, 2-SE, and 1-SE had a significant deterioration in marginal discoloration at the 18-month recall. The 36-month clinical performance of Scotchbond Universal Adhesive improved for both etch-and-rinse strategies. Phosphoric acid etching is still recommended to provide retention to composite restorations in NCCLs.

Accuracy of CAD/CAM-fabricated bite splints: milling vs 3D printing

Abstract: The aim of this study was to investigate the accuracy of CAD/CAM-fabricated bite splints in dependence of fabrication method (milling vs 3D printing), positioning (horizontal vs vertical), selection of material, and method of deviation measurement. Bite splints were 3D-printed in either horizontal or vertical position (n = 10) using four different resins (Dental LT, Ortho Clear, Freeprint Splint, V-Splint). As control, ten bite splints were fabricated by CNC milling (ProArt CAD Splint). The splints were scanned and deviations between the CAD-file (trueness) and between each other within one group (precision) were measured by two different software applications and methods (cloud-to-cloud vs cloud-to-mesh). Data were analyzed using univariate analysis, Kolmogorov-Smirnov, Kruskal-Wallis, and Mann-Whitney U tests. The highest impact on accuracy was exerted by the selection of the material (trueness: ηP2 = 0.871, P < 0.001; precision: ηP2 = 0.715, P < 0.001). Milled splints showed the highest trueness (P < 0.01) but not the highest precision at the same time. Horizontally positioned 3D-printed bite splints showed the least deviations in terms of trueness while vertical positioning resulted in the highest precision. The cloud-to-cloud method showed higher measured deviations than the other methods (P < 0.001–P = 0.002). Milled splints show higher trueness than 3D-printed ones, while the latter reveal higher reproducibility. The calculated deviations vary according to the measurement method used. In terms of accuracy, milled and 3D-printed bite splints seem to be of equal quality.

Non-surgical therapeutic outcomes of peri-implantitis: 12-month results

Abstract: To assess the clinical and radiographic outcomes of implants treated by means of non-surgical debridement with systemic antibiotic therapy. A prospective case series study evaluating the 12-month clinical and radiographic outcomes of peri-implantitis lesions treated with ultrasonic scaler debridement, a glycine air abrasive, and metronidazole followed by supportive maintenance. Clinical and radiographic variables and success criteria were defined a priori. Overall, 21 patients were included. One implant failed during the study period (implant survival rate 95.24%). Substantial changes occurred at 12 months in all the clinical and radiographic variables, reaching strong statistical significance in the majority of them. According to the success criteria applied, 40.90% of the peri-implantitis were arrested and resolved, while 59.1% presented with at least one probed site with bleeding on probing (BoP). Moreover, 95.45% exhibited peri-implant pocket depth (PPD) < 5 mm at the end of the study. None of the implants presented with progressive bone loss. Non-surgical therapy of peri-implantitis is effective to arrest progressive bone loss, reduce PPD and suppuration, and achieve radiographic bone fill in the majority of cases. Nevertheless, it failed to be completely efficacious in the achievement of successful therapeutic outcomes as BoP remained frequently present. Non-surgical therapy achieved significant clinical and radiological improvements.

The impact of nonsurgical periodontal treatment on oral health-related quality of life: a systematic review and meta-analysis

Abstract: To estimate the impact of nonsurgical periodontal treatment (NSPT) on patients’ oral health-related quality of life (OHRQoL). The focused question for this systematic review was: in adults patients with periodontitis, does NSPT improve oral health-related quality of life? Five databases (PubMed, CIHNL, EMBASE, LILACS and CENTRAL) were searched up to April 2019 (PROSPERO CRD42018103393). Intervention trials and cohort studies assessing the OHRQoL data of adults with periodontitis, enduring non-surgical periodontal treatment (NSPT) were eligible for inclusion. Subgroup random-effects meta-analysis was conducted methodically. Overall, 491 studies were retrieved, out of which 19 met the inclusion criteria. Two randomized clinical trials (RCTs) and ten cohort studies were further analysed. Seven cohort studies were included in the statistical analysis. Subgroup meta-analyses of cohort studies revealed that NSPT improves in average 2.49 (95% CI 0.95–4.02), 8.94 (95% CI 6.89–10.99) and 6.49 (95% CI 5.11–7.88) OHRQoL levels at 1–2 weeks, 3–4 weeks and 6–12 weeks of post-treatment, respectively. NSPT procedures greatly improve the oral health-related quality of life within a short time, remaining stable after 3 months of treatment. This systematic review brings forward summary evidence that NSPT improves the OHRQoL in adults with periodontitis from a patient-centred perception and remain stable in the short term.

The assessment of stress, depression, and inflammation as a collective risk factor for periodontal diseases: a systematic review.

Abstract: Objectives The purpose of this review was to provide a novel perspective utilizing an assessment of biomarkers to evaluate the impact of stress-related disorders on the progression of periodontal disease and evaluate the growing body of evidence of stress as a risk indicator for periodontal disease progression. Methods Cross-sectional, case-control, and biomarker studies associating psychological disorders and periodontal disease were included in the literature search. Computational studies, animal studies, reviews, and studies lacking healthy controls were excluded. Electronic and manual literature searches were conducted by two independent reviewers in several databases as well as a manual search for relevant articles published up to January 2018. Results Twenty-six articles fulfilled the inclusion criteria and were included in the qualitative synthesis. Relationships between stress-related disorders and serum and salivary biomarkers such as cortisol, dehydroepiandrosterone (DHEA), chromogranin A (CgA), and pro-inflammatory cytokines were identified. Conclusions The use of salivary pro-inflammatory cytokines alone is not sufficient for the identification of periodontal disease severity/progression with or without the presence of stress-associated diseases. Keeping in mind the limitations of this review, a positive qualitative correlation was observed in the literature among stress-related biomarkers and the severity of periodontal disease. This correlation may serve as an important reporter of patient susceptibility for periodontal breakdown in the future. Clinical relevance Stress-related disorders should be included in the list of globally screened diseases because it can change the biochemistry of both the local periodontal microenvironment as well as the global systemic inflammatory burden.

COVID-19 outbreak: succinct advice for dentists and oral healthcare professionals.

Abstract: Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) [1]. The virus, identified as the causative agent for a cluster of pneumonia cases initially detected in Wuhan City, China, in late 2019, was isolated and its sequence made available on January 7 and 12, 2020, respectively [2]. Phylogenetic data implicate a zoonotic origin of the virus, which is closely related to two bat-derived severe acute respiratory syndrome (SARS)–like coronaviruses, but more distant from SARS-CoV and Middle East respiratory syndrome (MERS)-CoV [3]. The study of community transmission and family clusters of the disease, as well as the rapid spread of infection across the world, has soon provided key insights to support the existence of person-to-person transmission [4]. According to an early scoping review [5], reported symptoms of COVID-19 range from mild to severe, with some cases (1–3%) resulting in death, particularly in adult and elder individuals. The most commonly reported clinical manifestations are fever, cough, myalgia or fatigue, pneumonia, and complicated dyspnea. Current estimates of COVID-19’s case fatality rate suggest that the novel coronavirus is less deadly than the pathogens behind other large-scale outbreaks, such as of SARS, MERS, and Ebola. However, the infection seems to spread much faster than SARS, MERS, and seasonal influenza [6]. The virus’s basic reproduction number (R0)—the number of people on average one infected person will pass the virus to—is comparatively high, and WHO has published their estimation of R0 to be 2.0–2.5 using early information. The Centers for Disease Control and Prevention (CDC) in the USA has indicated that certain healthcare workers, including dentists, are at a “very high” risk of exposure to SARSCoV-2. In particular, it appears that working in high-risk departments, longer duty hours, and suboptimal hand hygiene after contacting with patients are linked to COVID-19 [7]. Dental professionals are not only at high risk for infection but also can become potential carriers of the disease. Hence, the aim of this review was to collect currently available evidence and resources to help dental professionals minimize the spread of SARS-CoV-2. While this information is current up toMarch 2020, it is likely that new information will emerge in the next weeks.

Synergistic potential of 1α,25-dihydroxyvitamin D3 and calcium–aluminate–chitosan scaffolds with dental pulp cells

Abstract: This study aimed to develop a porous chitosan–calcium–aluminate scaffold (CH-AlCa) in combination with a bioactive dosage of 1α,25-dihydroxyvitamin D3 (1α,25VD), to be used as a bioactive substrate capable to increase the odontogenic potential of human dental pulp cells (HDPCs). The porous CH-AlCa was developed by the incorporation of an AlCa suspension into a CH solution under vigorous agitation, followed by phase separation at low temperature. Scaffold architecture, porosity, and calcium release were evaluated. Thereafter, the synergistic potential of CH-AlCa and 1 nM 1α,25VD, selected by a dose–response assay, for HDPCs seeded onto the materials was assessed. The CH-AlCa featured an organized and interconnected pore network, with increased porosity in comparison with that of plain chitosan scaffolds (CH). Increased odontoblastic phenotype expression on the human dental pulp cell (HDPC)/CH and HDPC/CH-AlCa constructs in the presence of 1 nM 1α,25VD was detected, since alkaline phosphatase activity, mineralized matrix deposition, dentin sialophosphoprotein/dentin matrix acidic phosphoprotein 1 mRNA expression, and cell migration were overstimulated. This drug featured a synergistic effect with CH-AlCa, since the highest values of cell migration and odontoblastic markers expression were observed in this experimental condition. The experimental CH-AlCa scaffold increases the chemotaxis and regenerative potential of HDPCs, and the addition of low-dosage 1α,25VD to this scaffold enhances the potential of these cells to express an odontoblastic phenotype. Chitosan scaffolds enriched with calcium–aluminate in association with low dosages of 1α,25-dihydroxyvitamin D3 provide a highly bioactive microenvironment for dental pulp cells prone to dentin regeneration, thus providing potential as a cell-free tissue engineering system for direct pulp capping.

Bleaching-induced tooth sensitivity with application of a desensitizing gel before and after in-office bleaching: a triple-blind randomized clinical trial.

Abstract: This randomized triple-blind clinical trial, split-mouth design, evaluated the application effect of the desensitizing gel before and after in-office bleaching on tooth sensitivity. In one group, the desensitizing gel was applied for 10 min before the bleaching with 35% hydrogen peroxide, and then application of placebo gel after (n = 90). In the other group, the desensitizing gel was applied before and after the bleaching procedure for 10 min (n = 90). The primary outcome was pain intensity assessed with a numeric rating scale and a visual analog scale. Color was evaluated by means of a digital spectrophotometer and a shade guides. The proportion of patients that experienced pain in the side of before application was 90% (95% CI 82 to 94.6%), while the side of before and after was 93% (95% CI 86.2 to 96.9%), without significant difference between groups (OR = 0.25; 95% CI 0.005 to 2.52; p = 0.37). Pain was correlated in both groups, for the NRS scale (p 0.45). The application of the desensitizing agent did not influence the effectiveness of bleaching, but it was not efficient in reducing the sensitivity, when applied before the procedure, or before and after. The use of a desensitizing gel before or after in-office bleaching does not reduce incidence or intensity of tooth sensitivity.

Clinical and histological reaction of periodontal tissues to subgingival resin composite restorations

Abstract: To compare the clinical and histological response of supracrestal periodontal tissues to subgingival composite restorations versus natural root surfaces In 29 subjects with a single tooth requiring subgingival restorations, a deep margin elevation (DME) procedure with composite resin was applied. Full-mouth plaque score (FMPS), full-mouth bleeding score (FMBS), and focal probing depth (PD) were measured at baseline, before DME, and after 3 months. The distance between the coronal marked (CM) point to the apical margin of the composite reconstruction (AMR), at baseline, and to the tip of the periodontal probe inserted to reach the bottom of the sulcus (APP), 3 months later, was measured. An all-around secondary flap, harvested to ensure the subsequent single-crown prosthetic rehabilitation was histologically processed. The histological inflammation degree was evaluated in areas of gingival tissues adjacent to the composite (group B) and adjacent to the natural surface of each single tooth (group A). Significant FMPS, FMBS, and PD decreases were observed (p 0.05). For the first time, this topic was clinically and histologically studied in humans. Subgingival restorations resulted compatible with gingival health, with levels similar to that of untreated root surfaces. Deep margin elevation procedure produces favorable clinical and histological outcomes allowing a routine utilization in reconstructive dentistry.

Randomised clinical trial investigating self-assembling peptide P11-4 in the treatment of early caries.

Abstract: This prospective, randomised, split-mouth, clinical trial compared the efficacy of the self-assembling peptide P11-4 to fluoride varnish in the treatment of early buccal carious lesions. Subjects presenting at least two clinically affected teeth were treated at D0 (day 0) and D90 with P11-4 (test) or fluoride varnish (control). At D180, fluoride varnish was applied on all study lesions. Standardised photographs were taken at D0, D30, D90, D180 and D360 and blindly morphometrically assessed. Hierarchical linear models (HLM) under allowance of confounders were used to compare the decrease in size between test and control groups. The visual analog scale (VAS) and Global Impression of Change Questionnaire (GICQ) were used as clinical assessments. Overall, 37 subjects (13–36 years) with 90 early carious lesions were included. HLM analysis showed a significant difference between test and control groups, indicating a decrease in test lesions and stabilisation of control lesions size (p = 0.001). The test lesion’s mean size (SD) relative to baseline decreased to D30 = 0.936(0.127), D90 = 0.874(0.173), D180 = 0.844(0.215) and D360 = 0.862(0.352), whereas control lesions remained stable at D30 = 1.018(0.209), D90 = 1.013(0.207), D180 = 1.029(0.235) and D360 = 1.068(0.401). The effect sizes ranged from 0.47 to 0.82. Within the limits of this study, it was shown that the size of early carious lesions treated with P11-4 was significantly reduced; this result was superior to that of fluoride varnish treatment (DRKS00012941). The self-assembling peptide P11-4 is the first caries treatment approach aiming to regenerate decayed enamel. P11-4 initiates formation of de novo hydroxyapatite in the depth of early carious lesions, adding a new advanced therapy option for preventive dentistry.

Is there association between stress and periodontitis

Abstract: This study estimated the association between stress and periodontitis. A cross-sectional study was conducted with a sample of 621 individuals. Information about individuals was obtained through a questionnaire. Stress was evaluated using the Perceived Stress Scale. The diagnosis of periodontitis was based on a complete periodontal examination including clinical attachment level, probing depth, and bleeding on probing. Prevalence ratios (PR), crude and adjusted, and their respective 95% confidence intervals (95%CI) were estimated by Poisson regression analysis. In the final sample, 48.47% (301) of the individuals were classified as having stress, of which, 23.92% (72) had the diagnosis of periodontitis. Association measurements between stress and probing depth ≥ 4 mm (PRadjusted = 1.28, 95%CI [1.04 to 1.58]), stress and clinical attachment level ≥ 5 mm (PRadjusted = 1.15, 95%CI [1.01 to 1.31]), and stress and periodontitis (PRadjusted = 1.36, 95%CI [1.01 to 1.83]) showed that the frequency of these outcomes among those exposed to stress was 15–36% higher than those without the condition of stress, after adjustment for age, sex, schooling level, current smoking habit, pulmonary disease, and body mass index. The findings showed positive association between exposure to stress and the presence of periodontitis, reaffirming the need to prevent and control stress. Although there are limitations in this study, the results showed that an association exists between stress and periodontitis, signaling the necessity of a multidisciplinary attention when considering the psychological status in the management of oral and general health conditions of the individual.

Influence of accelerated ageing on the physical properties of CAD/CAM restorative materials.

Abstract: This study aims to investigate the influence of thermocycling on the physical properties of different CAD/CAM restorative materials and assess their ability to maintain energy dissipation capacities and damping effects. The results of a 3-point bending test were used to calculate flexural strength (FS), modulus of elasticity (ME), modulus of toughness (MT) and elastic recovery (ER) for three ceramic, twelve composite and five polymer-based materials. Specimens (n = 10, 4.0 × 1.5 × 17.0 mm3) were loaded until rupture after water storage (24 h; 37.0 ± 1.0 °C) or thermocycling (5000 cycles; 5–55 °C). Statistical data analysis was performed using parametric statistics (p = 0.05). Thermocycling had no significant influence on any investigated properties of ceramic materials (p > 0.05). Hybrid composites showed significant differences between water storage and thermocycling (p < 0.05), with the exception of FS of Tetric CAD. Similarly, ME with AMBARINO High-Class, CERASMART, Tetric CAD and Vita Enamic and MT and ER with Paradigm and Tetric CAD were not affected. For polymer-based materials, significant differences were found with the exceptions of FS (PEEK-OPTIMA, Telio CAD), ME (M-PM Disc, PEEK-OPTIMA, Telio CAD, Vita CAD-Temp), MT (Telio CAD) and ER (Telio CAD). The material properties of composite and polymer-based CAD/CAM materials were susceptible to degradation processes induced by thermocycling. Only Telio CAD and Tetric CAD showed no significant effects like all ceramic materials, thus preserving their inherent ability to elastically and plastically dissipate energy. A careful material selection is advisable when planning CAD/CAM restorations as remarkable differences may exist in the durability of physical characteristics through the impact of water.

An international survey on the use of calcium silicate-based sealers in non-surgical endodontic treatment

Abstract: To gain insight on the current clinical usage of bioceramic root canal sealers (BRCS) by general dental practitioners (GDPs) and endodontic practitioners (EPs) and to determine if BRCS clinical application is in accordance with the best available evidence. An online questionnaire of 18 questions addressing BRCS was proposed to 2335 dentists via a web-based educational forum. Participants were asked about socio-demographic data, clinical practice with BRCS, and their motivation for using BRCS. Statistical analysis (chi-squared test or Fisher’s exact test) was applied, as appropriate, to assess the association between the variable categories (p value < 0.05). The response rate was 28.91%. Among respondents, 94.8% knew BRCS (EPs more than GDPs, p < 0.05) and 51.70% were using BRCS. The primary reason for using BRCS was their belief of its improved properties (87.7%). Among BRCS users, single-cone technique (SCT) was the most employed obturation method (63.3%) which was more applied by GDPs (p < 0.05); EPs utilized more of the thermoplasticized obturation techniques (p < 0.05). A proportion of 38.4% of BRCS users indicated the usage of SCT with BRCS regardless of the root canal anatomy (GDPs more than EPs p < 0.05) and 55.6% considered that BRCS may influence their ability to re-establish apical patency during retreatment (GDPs more than EPs p < 0.05). This study highlights wide variation in the clinical use of BRCS which is not in accordance with the current literature. This inconsistency among EPs and GDPs on BRCS clinical application requires further clarifications to better standardize their use and improve their future evaluation.

Effect of treatment with a full-occlusion biofeedback splint on sleep bruxism and TMD pain: a randomized controlled clinical trial

Abstract: OBJECTIVES The purpose of the present study was to analyze treatment outcome with a full-occlusion biofeedback (BFB) splint on sleep bruxism (SB) and TMD pain compared with treatment with an adjusted occlusal splint (AOS). MATERIALS AND METHODS Forty-one patients were randomly allocated to a test (BFB) or a control (AOS) group and monitored over a 3-month period. Output variables were frequency and duration of bruxing events (bursts) and various pain symptoms. RESULTS The BFB group showed a statistically significant reduction in the frequency and duration of bursts and a statistically significant improvement in the patients' global well-being and the facial muscle pain parameter. After the treatment was stopped, the BFB group showed a statistically significant reduction in the average and maximum duration but no statistically significant change in the frequency of bursts. CONCLUSIONS The tested BFB splint is highly effective in reducing SB at the subconscious level, i.e., without waking the patient, and in achieving improvements in global pain perception. The results suggest that the BFB splint also provides a better treatment option for bruxism-related pain than an AOS. However, further research is needed, and specifically studies with a larger patient population displaying higher levels of pain at baseline. CLINICAL RELEVANCE By reducing burst duration and therefore the pathological load on the masticatory apparatus, the BFB splint reduces TMD and bruxism-related symptoms and improves patients' physical well-being. In the long term, this could prevent damage to the TMJ. This study confirms the effectiveness and safety of this splint. THE UNIVERSAL TRIAL NUMBER U1111-1239-2450 DRKS-ID REGISTRATION: DRKS00018092.